BANGKOK — When the Thai military says cadets can’t bring phones to training, they mean it.

A video clip that has ignited social media in Thailand this week shows what happened to some officers-in-training who broke that rule.

The video, dubbed “Soldiers Must Endure,” shows a row of uniformed naval cadets with their iPhones and Samsung smartphones on the ground, each one beside a concrete block.

“You just bought this, right? Expensive, eh?” says the voice of a commanding officer who asks each trainee to state the make of his phone and then orders them to bend down and “Smash it!”

The video has been viewed hundreds of thousands of times on Facebook, YouTube and popular Thai social media forums in the past few days, drawing mostly criticism that the punishment doesn’t fit the crime. Many comments posted online suggested the military confiscate the pricey phones from rule breakers and return them at the end of the term, rather than destroying them.

Others half-jokingly called it a form of torture in Thailand, where people are extremely attached to their smartphones. The Southeast Asian country is one of the world’s biggest users of social media and has repeatedly claimed top spots on annual lists of the world’s most Instagrammed places.

It was not clear who took the video, which was filmed vertically, apparently using a phone.

The Thai navy issued a statement to “clarify” what happened at its Communications and Information Technology School, which has a rule forbidding students from carrying cellphones on school grounds that is frequently violated.

Teachers at the school came up with an “honor system” whereby those who break the rule “destroy their phones voluntarily,” said the statement posted on the website of the navy’s radio station, Voice of Navy.

“This ‘honor system’ was not recognized by the school and it was not school policy. Therefore, the school has ordered this form of punishment to stop,” the statement said.

“That a military school focusing on communications and information technology does not view mobile phones as learning tools, but obstacles that must be banned, says a lot about how much the military has to do to catch up with the world,” the commentary said.